Multi-bombe connecting device for liquefied petroleum injection vehicle

ABSTRACT

A multi-bombe connecting device has a main bombe with a fuel pump and one or more auxiliary bombes. A fuel pipe connects the main bombe and the auxiliary bombe and allows fuel to flow between the main bombe and the auxiliary bombe. A fuel isolating device closes the fuel pipe when the vehicle ascends or descends a slope. The auxiliary bombe is disposed lower than the main bombe. The fuel isolating device includes a ball, a panel attached to a rod, a spring attached to the panel, a switch, a throttle valve actuator, and a throttle valve.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to Korean Application No.10-2003-0065541, filed on Sep. 22, 2003, the disclosure of which isincorporated fully herein by reference.

FIELD OF THE INVENTION

The present invention relates to a Liquefied Petroleum Injection (LPI)vehicle mounted with a plurality of bombes. More particularly, thepresent invention relates to a device connecting the plurality of bombesto enable the fuel to flow between the plurality of bombes.

BACKGROUND OF THE INVENTION

In Liquefied Petroleum Gas (LPG) vehicles, the LPG provided from a bombeis typically injected in a gaseous state to the engine through avaporizer and a mixer. However, LPG vehicles having the system describedabove have many drawbacks relating to engine output, fuel consumption,starting at low temperatures, engine exhaust gas, and the like. Thus,vehicles using LPI systems have recently been developed.

In LPI vehicles, the liquefied petroleum (LP) is injected by using afuel pump built into the bombe, and the injector injects the fuel in aliquid state into the engine. This results in excellent engine output,fuel consumption, starting at low temperatures, engine exhaust gas, andthe like. LPI vehicles generally require a plurality of bombes, and thefuel pump is attached only to one of the plurality of bombes. Theremaining bombes provide fuel via the bombe attached to the fuel pump.The drawback of this configuration is that when the LPI vehicle mountedwith a plurality of bombes ascends or descends a slope withoutsufficient fuel, the fuel flows downward and becomes concentrated inonly one bombe, which usually is not the bombe attached to the fuelpump. This causes a shortage of fuel in the fuel pump-attached bombe,which, in turn, causes a shortage of fuel to the engine.

SUMMARY OF THE INVENTION

The present invention provides a multi-bombe connecting device for anLPI vehicle adapted to collect fuel in a fuel pump-attached bombe whenthe LPI vehicle mounted with a plurality of bombes ascends or descendson a slope, thereby preventing a fuel cut off phenomenon of the engine.The multi-bombe connecting device for an LPI vehicle comprises a mainbombe having a fuel pump therein and one or more auxiliary bombes. Afuel pipe connects the main bombe and the auxiliary bombe that allowsthe fuel to flow between the main bombe and the auxiliary bombe. A fuelisolating device closes the fuel pipe when a vehicle ascends or descendson a slope and the auxiliary bombe is positioned lower than the mainbombe. The present invention further comprises an auxiliary fuel pipeconnecting the main bombe and the auxiliary bombe and disposed higherthan the fuel pipe.

The fuel isolating device is composed of a housing including a passageslanted at a certain degree and containing a ball. A panel is slidablyinstalled in the passage and is attached in the rear to a rod. A springis attached to the panel to return the panel to its original positionwhen the panel is not contacting the ball. A switch that contacts therod controls activation of the fuel isolating device (“on” state) whenthe ball applies pressure to the panel as the vehicle ascends ordescends on a slope. A throttle valve opens and closes the fuel pipe. Athrottle valve actuator closes the fuel pipe by activating the throttlevalve when the switch is turned on.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the nature and objects of the presentinvention, reference should be made to the following detaileddescription with the accompanying drawings, in which:

FIG. 1 shows the structure of a multi-bombe connecting device for an LPIvehicle according to an embodiment of the present invention; and

FIG. 2 is a detailed view of a fuel isolating device.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The preferred embodiment of the present invention will now be describedin detail with reference to the accompanying drawings.

To achieve a minimal vehicle height as well as a low floor panel 1 of anLPI vehicle, the required fuel capacity cannot be satisfied by usingonly one bombe. Thus, an LPI vehicle, according to an embodiment of thepresent invention as shown in FIG. 1, comprises main bombe 20 having afuel pump 10 and two auxiliary bombes 30 and 32.

Main bombe 20 and auxiliary bombes 30 and 32 are respectively connectedvia fuel pipes 40 and 50, allowing fuel to flow between the threebombes. Fuel pipes 40 and 50 include fuel isolating devices 60 and 70,respectively. When one of the two auxiliary bombes 30 and 32 ispositioned lower than main bombe 20 as a vehicle ascends or descends ona slope, the fuel pipe connecting the relevant auxiliary bombe and themain bombe 20 is closed by the isolating device.

When auxiliary fuel pipes 80 and 90 connect main bombe 20 and auxiliarybombes 30 and 32 at a higher position than fuel pipes 40 and 50, and asufficient amount of fuel is in the bombes, fuel flow is improvedbetween each bombe 20, 30, and 32. Further, when the vehicle's fuel isnot low, auxiliary fuel pipes 80 and 90 facilitate movement of fuelbetween the bombes.

Referring to FIG. 2, fuel isolating devices 60 and 70 mounted at fuelpipes 40 and 50 are identical in shape but are placed in opposingdirections to each other (i.e., the two fuel isolating devices 60 and 70are mounted so that the ends with the balls face each other and the endswith the panels face away from each other). As shown in FIG. 2, housing62 includes passage 61 and is fixed to fuel pipe 40 via bracket 63.Passage 61 is formed at a certain incline (A=11.3°). Ball 64 is placedat a lower side in passage 61, while panel 65 formed at the rear sidewith a rod is slidably disposed at an upper side in passage 61. Spring66 positioned in passage 61 and attached to panel 65 to return panel 65toward the ball 64.

The upper side of passage 61 includes a switch 67 that activatesthrottle valve actuator 68. If a vehicle ascends or descends on a slope,causing ball 64 to roll toward and apply pressure to panel 65, the rodof panel 65 contacts switch 67, and throttle valve actuator 68 isturned. Once switch 67 is turned on, throttle valve actuator 68activates throttle valve 69 mounted on fuel pipe 40 and closes fuel pipe40.

Referring to FIG. 1, when an LPI vehicle having insufficient fuel(approximately 10% or less of the bombe capacity) moves on an ascendingslope (e.g. 11.3° or more), the fuel of main bombe 20 and auxiliarybombe 32 flows into auxiliary bombe 30. Fuel isolating device 60 mountedon fuel pipe 40 stops the fuel, which flows to auxiliary bombe 30 whenthe vehicle moves on an ascending slope, thereby preventing fuelshortage in main bombe 20. Provided that the LPI vehicle ascends on aslope, ball 64 of the fuel isolating device 60 presses the panel 65, andswitch 67 turns on by being contacted with the rod of panel 65. Throttlevalve actuator 68 activates throttle valve 69 mounted on fuel pipe 40and closes fuel pipe 40, thereby stopping the fuel flow through fuelpipe 40.

When the LPI vehicle moves on a flat surface, ball 64 of fuel isolatingdevice 60 shifts to its initial position, and the rod of panel 65 isseparated from the switch 67, and thus the switch 67 is turned off.Throttle valve actuator 68 activates throttle valve 69 and opens fuelpipe 40. Thus, the fuel can flow through fuel pipe 40.

On the other hand, if the LPI vehicle, having insufficient fuel(approximately 10% or less of the bombe capacity), moves on a descendingslope (e.g. 11.3° or more), the fuel of main bombe 20 and auxiliarybombe 30 flows to auxiliary bombe 32. Once fuel isolating device 70mounted on fuel pipe 50 stops fuel flow toward auxiliary bombe 32, fuelshortage resulting from a lack of fuel in main bombe 20 can beprevented.

In the above described embodiment of the present invention, twoauxiliary bombes are used. However, the number is not limited as long asthe bombe connecting device of the present invention is applied in anLPI vehicle using at least one auxiliary bombe.

As apparent from the foregoing, there is an advantage in the presentinvention, in that the fuel isolating devices prevents fuel shortage ina main bombe of an LPI vehicle when the vehicle ascends or descends aslope.

1. A multi-bombe connecting device for an LPI vehicle, comprising: amain bombe having a fuel pump therein; one or more auxiliary bombes; afuel pipe connecting said main bombe and said auxiliary bombe thatallows fuel to flow between said main bombe and said auxiliary bombe;and a fuel isolating device closing said fuel pipe when the vehicleascends or descends on a slope and said auxiliary bombe is disposedlower than said main bombe.
 2. The device in claim 1, wherein anauxiliary fuel pipe connecting said main bombe and said auxiliary bombeis disposed higher than said fuel pipe.
 3. The device in claim 1,wherein said fuel isolating device comprises: a housing containing apassage slanted at a certain degree; a ball placed inside said passage;a panel slidably installed in said passage and attached at the rear to arod; a spring returning said panel toward said ball; a switch that, whencontacting said rod, due to said ball's rolling onto and applyingpressure on said panel when the vehicle ascends a slope, turns on; athrottle valve configured to open and close said fuel pipe; and athrottle valve actuator closing said fuel pipe by activating saidthrottle valve when said switch is turned on.